# geometry

## English

### Etymology

From Old French géométrie, from Latin geōmetria, from Ancient Greek γεωμετρία (geōmetría, geometry, land-survey), from γεωμέτρης (geōmétrēs, land measurer), from γῆ (, earth, land, country) + -μετρία (-metría, measurement), from μέτρον (métron, a measure).

### Pronunciation

• (US) IPA(key): /d͡ʒiˈɑm.ə.tɹi/
•  Audio (US) (file)
• (UK) IPA(key): /d͡ʒiːˈɒm.ɪ.tɹi/, /ˈd͡ʒɒm.ɪ.tɹi/

### Noun

geometry (countable and uncountable, plural geometries)

1. () The branch of mathematics dealing with spatial relationships.
• 1925, René Descartes, “The Geometry of Rene Descartes”, in David Eugene Smith, Marcia Latham, transl., [1637, La Géométrie], Cosimo Classics, published 2007, page 2:
ANY problem in geometry can easily be reduced to such terms that a knowledge of the lengths of certain straight lines is sufficient for its construction.
2. (mathematics, often qualified in combination, countable) A mathematical system that deals with spatial relationships and that is built on a particular set of axioms; a subbranch of geometry which deals with such a system or systems.
• 1975 [Addison-Wesley], Eugene F. Krause, Taxicab Geometry, 1986, Dover, page 64,
Entire new geometries are also suggested by real-world cities.
• 2004, Judith Cederberg, A Course in Modern Geometries, Springer, page 1:
Finite geometries were developed in the late nineteenth century, in part to demonstrate and test the axiomatic properties of completeness, consistency, and independence.
• 2006, Mark Wagner, The Geometries of Visual Space, Lawrence Erlbaum Associates, page ix:
Previous theorists have often tried to test whether visual space is best described by a small set of traditional geometries, such as the Euclidean geometry most of us studied in High School or the hyperbolic and spherical geometries introduced by 19th-century mathematicians.
3. (countable) The observed or specified spatial attributes of an object, etc.
• 2003, Matt Welsh, Running Linux, page 74:
Also, certain SCSI controllers need to be told where to find drive geometry in order for Linux to recognize the layout of your drive.
• 2018 March 14, Roger Penrose, “'Mind over matter': Stephen Hawking – obituary”, in The Guardian:
He was extremely highly regarded, in view of his many greatly impressive, sometimes revolutionary, contributions to the understanding of the physics and the geometry of the universe.
4. () A mathematical object comprising representations of a space and of its spatial relationships.